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PML and scattering boundary condition in v4.3

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HI,

Is it necessary to define the outer boundaries of a PML as scattering boundary layers to obtain the losses of a leaky waveguide? In v3.5, I have defined the outer boundaries as perfect electric conductors (PEC) and still obtained the correct loss values. With v4.3, if I set the outer boundaries as PECs, I get only real valued effective index solutions and not complex ones, implying that the losses are zero.

Thanks.

3 Replies Last Post 16.08.2012, 08:26 GMT-4
Mette Marie Joergensen

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Posted: 1 decade ago 16.08.2012, 05:12 GMT-4
Hi Sonali,

I think that comsol 4.3 in some cases only return real values by default, which is different from version 3.5. So maybe you have to turn complex output values on.

BR, Mette

Hi Sonali, I think that comsol 4.3 in some cases only return real values by default, which is different from version 3.5. So maybe you have to turn complex output values on. BR, Mette

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Posted: 1 decade ago 16.08.2012, 06:56 GMT-4
Thanks, Mette. You are absolutely right. However, inspite of setting the option as <'complexout', 'on'>, the returned values are still real. And it seems like the losses that I get back by using the scattering boundary condition are not correct either.. I ma using the RF module to model a leaky dielectric waveguide.

Thanks.
Thanks, Mette. You are absolutely right. However, inspite of setting the option as , the returned values are still real. And it seems like the losses that I get back by using the scattering boundary condition are not correct either.. I ma using the RF module to model a leaky dielectric waveguide. Thanks.

Mette Marie Joergensen

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Posted: 1 decade ago 16.08.2012, 08:26 GMT-4
I have not tried my model with PML yet, so I do not have an answer. But it is an important issue. If you find a solution, please post it in here.

BR, Mette
I have not tried my model with PML yet, so I do not have an answer. But it is an important issue. If you find a solution, please post it in here. BR, Mette

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